Totally agree that you're over 500whp. I think you'll find though, that dropping an additional 2/10ths here and another 10th there is not super easy once you really get down to it. You'll find, to get better traction, it will have to be warmer out and that means a higher DA.
Food for thought, my truck weighs 6500lbs with me in it. Dynod last at 509whp, and was making a little more after (~530whp). I can't launch my truck, due to suspension set up and cut a 2.15 60ft and the Truck managed a 13.23 1.4 mile.
Please, trust me that I'm not trying to come across as negative. I've just watched time and time again, where folks compare to others (usually ones in Texas) and expect that they are going to see similar results. They end up frustrated in the end as expectations don't get met. You have a fast truck, tweak and work on technique and have some fun!